Manufacture of tempered glass



May 22, 1934. a L N 1,960,222

I MANUFACTURE OF TEMPERED GLASS Filed Oct. 6, 1931 2 Sheets-Sheet l r BY J ATTORNEYS.

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O QOOOOO Filed Oct. 6, 1951 o o o o o o.

o o o o o o I MANUFAFJ I QIRE OF TEMPERED GLASS o o 0 o o o o o o o o INVENTOR. ,Bermra Z019;

rQ'k I ATTORNEYS.

Patented May 22, 1934 UNITED STATES PATENT I OFFICE Anonyme des Manufactures des Glaces &

Produits Chimiques dc: Saint-Gobain, Chauny & Cirey, Paris, France Application October 6, 1931, Serial No. 567,286

In France October 22, I930 9 Claims.

In another application, (Serial No. 434,263), filed by me and Robert Touvay, March 8 1930 I have disclosed a method of tempering sheet glass by directing on the sheet, while highly 5 heated (in the case of ordinary window glass 550 to 620 0.), jets of air.

Experience has shown that sheets produced by the apparatus described'and shown in the aforesaid application are sometimes defective, in that when examined obliquely iridescent spots are visible where the jets stroke the surface of the sheets. The present invention has for its object to prevent the occurrence of such spots, and this I accomplish by causing the air jets to successively impinge on the sheets at different points. This may be accomplished in several difierent ways. Thus the air nozzles may be divided into two groups, the one group projecting its jets. on the sheets intermediate of points on which the other group projects its jets, and causing the air to alternately issue from the jets of the two series, or it may be accomplished by creating a relative movement between the air nozzles by which the jets are projected and the sheet, such motion having a component transverse to the direction in which the jets are projected, and for this purposemy invention consists in the features and .steps hereinafter described and claimed Referring to the accompanying drawings, in which similar parts are designated by similar marks oireference Figure 1 is a side view of one form of mechanism for carrying out this invention Figure 2 is an elevation of the jet projector of Figure 1.

Figures 3 and 4 are diagrammatic representations of'the results obtainedby using the structures shown in Figures 1 and 2.

Figure 5.shows a form of my invention in which a single series of air nozzles are shifted to distribute the point of impact. In F'gures 1 and 2, 1 represents a grill of pipes having air nozzles 1o therein and feeding air under pressure-by the pipe 1b, provided with a valve 1d, while 2 represents another pipe grill, with air nozzles 2a fed by the pipe 2b having the valve 2d. The nozzles 1a and 2a are staggered, and the valves 1d and 2d are mounted on a common shaft 3, which may be driven in any suitable areas 1e: be produced on each side of theplate A, suspended by the tongs If in Figure I. When the valve In; is closed and the valve 211 opened, cooling areas as 2e will be produced, the one series of areas being interposed between the others. When the valves are repeatedly opened and closed, a uniform chilling of each surface of the plate will. be produced, and it be found that the iridescence produced by prolonged projection of a jet on the same area will not be pro- 55 duced.

In lieu of the double sets of jets above described, a single series of nozzles may be em-- ployed, and their action spread over the plate by causing a relative lateral'movement between the plate and the nozzles. Figure 5- illustrates how this may be done by moving the nozzles. In the figure, 4 is an air box-having on one face thereof, a series of air nozzles 40: adapted to project I jets of air on the plate. The box is mounted for movement in a plane parallel with its surface by links 411, and may be given a. swinging movement in such plane by the connecting rod 4c, driven by a pin 4d,

Having thus described claim is:

1. The hereinbefore described method of tempering a glass sheet by directing jets of .cooling air thereon, which comprises shifting the point of impact of such jets on the sheet in sucha manner that the jets impinge on the same areas for only limited periods of time, then impinge an area interposed between the first areas, and then impinge on the first named areas.

2. An apparatus for tempering glass sheets comprising nozzles directing air jets against thesurface of the sheet, means for creating during the tempering a relative movement having a commyinvention what I ponent at right angles to the direction of the jets between the nozzles and the sheet and means fat supplying the nozzles with air cooler than the s eet.

3. In an apparatus for tempering glass sheets, the combination of air nozzles projecting jets of air at a constant angle against the sheet, means for changing, in a regular cycle, the points at which the jets impinge on the sheet and means for supplying the nozzles with air cooler than the sheet.

4. In an apparatus for tempering glass sheets, two series of air nozzles, the nozzles of one series being interposed between those of the other, and means for alternately projecting air jets from the nozzles of the two series. v v

5. In an apparatus for tempering glass sheets,

the combination with air nozzles, means for supporting a heated sheet of glassopposite the nozzles, and means for causing a cyclic relative motion between the nozzles and the glass sheet in a plane across the direction in which the jets are projected.

6. The hereinbefore described method of tempering a glass sheet which comprises repeatedly subjecting the same surface areas on thesheet to jets of air cooler than the sheet.

'7. The hereinbefore described method of tempering a glass sheet which comprises intermittently removing heat from surface areas of the sheet in repeated cycles.

8. The hereinhefore described method of tem- Ypering a glass sheet by directing simultaneously 

